diff --git a/chebai/preprocessing/bin/smiles_token/tokens.txt b/chebai/preprocessing/bin/smiles_token/tokens.txt
index bfb6b2a1..6f4c338e 100644
--- a/chebai/preprocessing/bin/smiles_token/tokens.txt
+++ b/chebai/preprocessing/bin/smiles_token/tokens.txt
@@ -761,6 +761,7 @@ p
 [Ta-]
 [6Li]
 [19O]
+[194Po]
 [Nb]
 [45Sc]
 [Nd]